32
32
#define _LARGEFILE_SOURCE
33
33
#define _FILE_OFFSET_BITS 64
35
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */
35
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY() */
37
#include <stdio.h> /* fprintf(), stderr, fwrite(),
39
#include <stdint.h> /* uint16_t, uint32_t */
40
#include <stddef.h> /* NULL, size_t, ssize_t */
41
#include <stdlib.h> /* free(), EXIT_SUCCESS, EXIT_FAILURE,
43
#include <stdbool.h> /* bool, true */
44
#include <string.h> /* memset(), strcmp(), strlen(),
45
strerror(), asprintf(), strcpy() */
46
#include <sys/ioctl.h> /* ioctl */
47
#include <sys/types.h> /* socket(), inet_pton(), sockaddr,
48
sockaddr_in6, PF_INET6,
49
SOCK_STREAM, INET6_ADDRSTRLEN,
50
uid_t, gid_t, open(), opendir(), DIR */
51
#include <sys/stat.h> /* open() */
52
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
53
struct in6_addr, inet_pton(),
55
#include <fcntl.h> /* open() */
56
#include <dirent.h> /* opendir(), struct dirent, readdir() */
57
#include <inttypes.h> /* PRIu16 */
58
#include <assert.h> /* assert() */
59
#include <errno.h> /* perror(), errno */
60
#include <time.h> /* time() */
41
#include <net/if.h> /* if_nametoindex */
42
#include <sys/ioctl.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
61
44
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
62
SIOCSIFFLAGS, if_indextoname(),
63
if_nametoindex(), IF_NAMESIZE */
64
#include <netinet/in.h>
65
#include <unistd.h> /* close(), SEEK_SET, off_t, write(),
66
getuid(), getgid(), setuid(),
68
#include <arpa/inet.h> /* inet_pton(), htons */
69
#include <iso646.h> /* not, and */
70
#include <argp.h> /* struct argp_option, error_t, struct
71
argp_state, struct argp,
72
argp_parse(), ARGP_KEY_ARG,
73
ARGP_KEY_END, ARGP_ERR_UNKNOWN */
76
/* All Avahi types, constants and functions
79
47
#include <avahi-core/core.h>
80
48
#include <avahi-core/lookup.h>
81
49
#include <avahi-core/log.h>
83
51
#include <avahi-common/malloc.h>
84
52
#include <avahi-common/error.h>
87
#include <gnutls/gnutls.h> /* All GnuTLS types, constants and
90
init_gnutls_session(),
92
#include <gnutls/openpgp.h> /* gnutls_certificate_set_openpgp_key_file(),
93
GNUTLS_OPENPGP_FMT_BASE64 */
54
/* Mandos client part */
55
#include <sys/types.h> /* socket(), inet_pton() */
56
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
57
struct in6_addr, inet_pton() */
58
#include <gnutls/gnutls.h> /* All GnuTLS stuff */
59
#include <gnutls/openpgp.h> /* GnuTLS with openpgp stuff */
61
#include <unistd.h> /* close() */
62
#include <netinet/in.h>
63
#include <stdbool.h> /* true */
64
#include <string.h> /* memset */
65
#include <arpa/inet.h> /* inet_pton() */
66
#include <iso646.h> /* not */
67
#include <net/if.h> /* IF_NAMESIZE */
96
#include <gpgme.h> /* All GPGME types, constants and
99
GPGME_PROTOCOL_OpenPGP,
70
#include <errno.h> /* perror() */
102
76
#define BUFFER_SIZE 256
105
#define PATHDIR "/conf/conf.d/mandos"
108
#define PATHDIR "/conf/conf.d/mandos"
109
#define SECKEY "seckey.txt"
110
#define PUBKEY "pubkey.txt"
78
static const char *keydir = "/conf/conf.d/mandos";
79
static const char *pubkeyfile = "pubkey.txt";
80
static const char *seckeyfile = "seckey.txt";
112
82
bool debug = false;
113
static const char mandos_protocol_version[] = "1";
114
const char *argp_program_version = "mandos-client 1.0";
115
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
117
/* Used for passing in values through the Avahi callback functions */
84
const char mandos_protocol_version[] = "1";
86
/* Used for passing in values through all the callback functions */
119
88
AvahiSimplePoll *simple_poll;
120
89
AvahiServer *server;
109
* Decrypt OpenPGP data using keyrings in HOMEDIR.
110
* Returns -1 on error
148
static bool init_gpgme(mandos_context *mc, const char *seckey,
149
const char *pubkey, const char *tempdir){
112
static ssize_t pgp_packet_decrypt (const char *cryptotext,
115
const char *homedir){
116
gpgme_data_t dh_crypto, dh_plain;
151
118
gpgme_error_t rc;
120
size_t plaintext_capacity = 0;
121
ssize_t plaintext_length = 0;
152
122
gpgme_engine_info_t engine_info;
156
* Helper function to insert pub and seckey to the enigne keyring.
158
bool import_key(const char *filename){
160
gpgme_data_t pgp_data;
162
fd = TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
168
rc = gpgme_data_new_from_fd(&pgp_data, fd);
169
if (rc != GPG_ERR_NO_ERROR){
170
fprintf(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
171
gpgme_strsource(rc), gpgme_strerror(rc));
175
rc = gpgme_op_import(mc->ctx, pgp_data);
176
if (rc != GPG_ERR_NO_ERROR){
177
fprintf(stderr, "bad gpgme_op_import: %s: %s\n",
178
gpgme_strsource(rc), gpgme_strerror(rc));
182
ret = TEMP_FAILURE_RETRY(close(fd));
186
gpgme_data_release(pgp_data);
191
fprintf(stderr, "Initialize gpgme\n");
125
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
197
131
if (rc != GPG_ERR_NO_ERROR){
198
132
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
199
133
gpgme_strsource(rc), gpgme_strerror(rc));
203
/* Set GPGME home directory for the OpenPGP engine only */
137
/* Set GPGME home directory for the OpenPGP engine only */
204
138
rc = gpgme_get_engine_info (&engine_info);
205
139
if (rc != GPG_ERR_NO_ERROR){
206
140
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
207
141
gpgme_strsource(rc), gpgme_strerror(rc));
210
144
while(engine_info != NULL){
211
145
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
212
146
gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
213
engine_info->file_name, tempdir);
147
engine_info->file_name, homedir);
216
150
engine_info = engine_info->next;
218
152
if(engine_info == NULL){
219
fprintf(stderr, "Could not set GPGME home dir to %s\n", tempdir);
223
/* Create new GPGME "context" */
224
rc = gpgme_new(&(mc->ctx));
225
if (rc != GPG_ERR_NO_ERROR){
226
fprintf(stderr, "bad gpgme_new: %s: %s\n",
227
gpgme_strsource(rc), gpgme_strerror(rc));
231
if (not import_key(pubkey) or not import_key(seckey)){
239
* Decrypt OpenPGP data.
240
* Returns -1 on error
242
static ssize_t pgp_packet_decrypt (const mandos_context *mc,
243
const char *cryptotext,
246
gpgme_data_t dh_crypto, dh_plain;
249
size_t plaintext_capacity = 0;
250
ssize_t plaintext_length = 0;
253
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
153
fprintf(stderr, "Could not set GPGME home dir to %s\n", homedir);
256
157
/* Create new GPGME data buffer from memory cryptotext */
175
/* Create new GPGME "context" */
176
rc = gpgme_new(&ctx);
177
if (rc != GPG_ERR_NO_ERROR){
178
fprintf(stderr, "bad gpgme_new: %s: %s\n",
179
gpgme_strsource(rc), gpgme_strerror(rc));
180
plaintext_length = -1;
274
184
/* Decrypt data from the cryptotext data buffer to the plaintext
276
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
186
rc = gpgme_op_decrypt(ctx, dh_crypto, dh_plain);
277
187
if (rc != GPG_ERR_NO_ERROR){
278
188
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
279
189
gpgme_strsource(rc), gpgme_strerror(rc));
280
190
plaintext_length = -1;
282
gpgme_decrypt_result_t result;
283
result = gpgme_op_decrypt_result(mc->ctx);
285
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
287
fprintf(stderr, "Unsupported algorithm: %s\n",
288
result->unsupported_algorithm);
289
fprintf(stderr, "Wrong key usage: %u\n",
290
result->wrong_key_usage);
291
if(result->file_name != NULL){
292
fprintf(stderr, "File name: %s\n", result->file_name);
294
gpgme_recipient_t recipient;
295
recipient = result->recipients;
297
while(recipient != NULL){
298
fprintf(stderr, "Public key algorithm: %s\n",
299
gpgme_pubkey_algo_name(recipient->pubkey_algo));
300
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
301
fprintf(stderr, "Secret key available: %s\n",
302
recipient->status == GPG_ERR_NO_SECKEY
304
recipient = recipient->next;
309
191
goto decrypt_end;
313
195
fprintf(stderr, "Decryption of OpenPGP data succeeded\n");
199
gpgme_decrypt_result_t result;
200
result = gpgme_op_decrypt_result(ctx);
202
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
204
fprintf(stderr, "Unsupported algorithm: %s\n",
205
result->unsupported_algorithm);
206
fprintf(stderr, "Wrong key usage: %d\n",
207
result->wrong_key_usage);
208
if(result->file_name != NULL){
209
fprintf(stderr, "File name: %s\n", result->file_name);
211
gpgme_recipient_t recipient;
212
recipient = result->recipients;
214
while(recipient != NULL){
215
fprintf(stderr, "Public key algorithm: %s\n",
216
gpgme_pubkey_algo_name(recipient->pubkey_algo));
217
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
218
fprintf(stderr, "Secret key available: %s\n",
219
recipient->status == GPG_ERR_NO_SECKEY
221
recipient = recipient->next;
316
227
/* Seek back to the beginning of the GPGME plaintext data buffer */
317
228
if (gpgme_data_seek(dh_plain, (off_t) 0, SEEK_SET) == -1){
318
perror("gpgme_data_seek");
229
perror("pgpme_data_seek");
319
230
plaintext_length = -1;
320
231
goto decrypt_end;
323
234
*plaintext = NULL;
325
plaintext_capacity = adjustbuffer(plaintext,
326
(size_t)plaintext_length,
236
plaintext_capacity = adjustbuffer(plaintext, (size_t)plaintext_length,
327
237
plaintext_capacity);
328
238
if (plaintext_capacity == 0){
329
239
perror("adjustbuffer");
404
312
/* OpenPGP credentials */
405
gnutls_certificate_allocate_credentials(&mc->cred);
406
if (ret != GNUTLS_E_SUCCESS){
407
fprintf (stderr, "GnuTLS memory error: %s\n", /* Spurious
313
if ((ret = gnutls_certificate_allocate_credentials (&mc->cred))
314
!= GNUTLS_E_SUCCESS) {
315
fprintf (stderr, "GnuTLS memory error: %s\n",
409
316
safer_gnutls_strerror(ret));
410
gnutls_global_deinit ();
415
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
416
" secret key %s as GnuTLS credentials\n", pubkeyfilename,
321
fprintf(stderr, "Attempting to use OpenPGP certificate %s"
322
" and keyfile %s as GnuTLS credentials\n", pubkeyfile,
420
326
ret = gnutls_certificate_set_openpgp_key_file
421
(mc->cred, pubkeyfilename, seckeyfilename,
422
GNUTLS_OPENPGP_FMT_BASE64);
327
(mc->cred, pubkeyfile, seckeyfile, GNUTLS_OPENPGP_FMT_BASE64);
423
328
if (ret != GNUTLS_E_SUCCESS) {
425
330
"Error[%d] while reading the OpenPGP key pair ('%s',"
426
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
427
fprintf(stderr, "The GnuTLS error is: %s\n",
331
" '%s')\n", ret, pubkeyfile, seckeyfile);
332
fprintf(stdout, "The GnuTLS error is: %s\n",
428
333
safer_gnutls_strerror(ret));
432
337
/* GnuTLS server initialization */
434
339
if (ret != GNUTLS_E_SUCCESS) {
435
340
fprintf (stderr, "Error in GnuTLS DH parameter initialization:"
436
341
" %s\n", safer_gnutls_strerror(ret));
439
344
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
440
345
if (ret != GNUTLS_E_SUCCESS) {
441
346
fprintf (stderr, "Error in GnuTLS prime generation: %s\n",
442
347
safer_gnutls_strerror(ret));
446
351
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
452
gnutls_certificate_free_credentials(mc->cred);
453
gnutls_global_deinit();
454
gnutls_dh_params_deinit(mc->dh_params);
458
static int init_gnutls_session(mandos_context *mc,
459
gnutls_session_t *session){
356
static int init_gnutls_session(mandos_context *mc, gnutls_session_t *session){
461
358
/* GnuTLS session creation */
462
359
ret = gnutls_init(session, GNUTLS_SERVER);
824
732
char *connect_to = NULL;
825
char tempdir[] = "/tmp/mandosXXXXXX";
826
733
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
827
const char *seckey = PATHDIR "/" SECKEY;
828
const char *pubkey = PATHDIR "/" PUBKEY;
830
734
mandos_context mc = { .simple_poll = NULL, .server = NULL,
831
.dh_bits = 1024, .priority = "SECURE256"
832
":!CTYPE-X.509:+CTYPE-OPENPGP" };
833
bool gnutls_initalized = false;
834
bool gpgme_initalized = false;
735
.dh_bits = 1024, .priority = "SECURE256"};
837
struct argp_option options[] = {
838
{ .name = "debug", .key = 128,
839
.doc = "Debug mode", .group = 3 },
840
{ .name = "connect", .key = 'c',
841
.arg = "ADDRESS:PORT",
842
.doc = "Connect directly to a specific Mandos server",
844
{ .name = "interface", .key = 'i',
846
.doc = "Interface that will be used to search for Mandos"
849
{ .name = "seckey", .key = 's',
851
.doc = "OpenPGP secret key file base name",
853
{ .name = "pubkey", .key = 'p',
855
.doc = "OpenPGP public key file base name",
857
{ .name = "dh-bits", .key = 129,
859
.doc = "Bit length of the prime number used in the"
860
" Diffie-Hellman key exchange",
862
{ .name = "priority", .key = 130,
864
.doc = "GnuTLS priority string for the TLS handshake",
869
error_t parse_opt (int key, char *arg,
870
struct argp_state *state) {
871
/* Get the INPUT argument from `argp_parse', which we know is
872
a pointer to our plugin list pointer. */
874
case 128: /* --debug */
877
case 'c': /* --connect */
880
case 'i': /* --interface */
883
case 's': /* --seckey */
886
case 'p': /* --pubkey */
889
case 129: /* --dh-bits */
738
/* Temporary int to get the address of for getopt_long */
739
int debug_int = debug ? 1 : 0;
741
struct option long_options[] = {
742
{"debug", no_argument, &debug_int, 1},
743
{"connect", required_argument, NULL, 'c'},
744
{"interface", required_argument, NULL, 'i'},
745
{"keydir", required_argument, NULL, 'd'},
746
{"seckey", required_argument, NULL, 's'},
747
{"pubkey", required_argument, NULL, 'p'},
748
{"dh-bits", required_argument, NULL, 'D'},
749
{"priority", required_argument, NULL, 'P'},
752
int option_index = 0;
753
ret = getopt_long (argc, argv, "i:", long_options,
891
mc.dh_bits = (unsigned int) strtol(arg, NULL, 10);
780
mc.dh_bits = (unsigned int) strtol(optarg, NULL, 10);
893
782
perror("strtol");
894
783
exit(EXIT_FAILURE);
897
case 130: /* --priority */
787
mc.priority = optarg;
905
return ARGP_ERR_UNKNOWN;
910
struct argp argp = { .options = options, .parser = parse_opt,
912
.doc = "Mandos client -- Get and decrypt"
913
" passwords from a Mandos server" };
914
ret = argp_parse (&argp, argc, argv, 0, 0, NULL);
915
if (ret == ARGP_ERR_UNKNOWN){
916
fprintf(stderr, "Unknown error while parsing arguments\n");
917
exitcode = EXIT_FAILURE;
922
/* If the interface is down, bring it up */
924
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
927
exitcode = EXIT_FAILURE;
930
strcpy(network.ifr_name, interface);
931
ret = ioctl(sd, SIOCGIFFLAGS, &network);
933
perror("ioctl SIOCGIFFLAGS");
934
exitcode = EXIT_FAILURE;
937
if((network.ifr_flags & IFF_UP) == 0){
938
network.ifr_flags |= IFF_UP;
939
ret = ioctl(sd, SIOCSIFFLAGS, &network);
941
perror("ioctl SIOCSIFFLAGS");
942
exitcode = EXIT_FAILURE;
946
ret = TEMP_FAILURE_RETRY(close(sd));
791
/* getopt_long() has already printed a message about the
792
unrcognized option, so just exit. */
796
/* Set the global debug flag from the temporary int */
797
debug = debug_int ? true : false;
800
pubkeyfile = combinepath(keydir, pubkeyfile);
801
if (pubkeyfile == NULL){
802
perror("combinepath");
803
exitcode = EXIT_FAILURE;
807
seckeyfile = combinepath(keydir, seckeyfile);
808
if (seckeyfile == NULL){
809
perror("combinepath");
813
ret = init_gnutls_global(&mc);
815
fprintf(stderr, "init_gnutls_global\n");
955
822
ret = setuid(uid);
957
824
perror("setuid");